1. Technical Field of the Invention
The present invention relates to a crawler shoe used for application to a crawler vehicle such as a snow mobile, construction vehicle or a farm vehicle. More specifically, the present invention relates to a crawler shoe comprising shoe members, each having a rubber pad attached on a ground contacting surface thereof, the shoe members being connected with each other by coupling links provided on a shoe plate.
2. Background Art
Crawler vehicles having crawlers or endless tracks have been frequently used as construction vehicles or farm vehicles which are often used at muddy places, or as snow mobiles which often travel on slippery slanted snow surfaces. In order to minimize noise and prevent road surfaces from being damaged, metal members used on the ground contacting surface of a crawler are increasingly replaced by rubber members.
Shoe members such as rubber pads are installed to shoe plates (track blocks) to form various structures.
FIG. 6 shows an example of the installation structures which are disclosed in Japanese Kokai Publication Hei 8 (1996)-58647. It is disclosed in the publication that a core 103, which has hooks 105 and 106 on both ends and a rubber member 104 adhered on the back surface, is installed to shoe plates 102. The shoe plates 102 are linked with each other by track links 101, so that an endless belt is formed. First, the slightly longer hook 106 of the core 103 at the right side engages with the right end of the shoe plate 102; the core 103 is moved to the left; the hook 105 of the core 103 at the left side is engaged with the left end of the shoe plate 102; and then the core 103 is slid to the right. Accordingly, a vacant space 107 is formed between the inner face of the hook 106 and the right edge of the shoe plate 102. Afterwards, a lock pin 108 is driven into the vacant space 107 in a driving direction (direction crossing the sheet) to fix the core 103 with the shoe plate 102.
In the installation where hooks 105 and 106 in a pair are prepared at both ends of the core 103 for the installation of a shoe plate, it is necessary to slide the core 103 to the left and tight with respect to the shoe plate 102, and to drive the lock pin 108 into the vacant space 107. In this case, the vacant space 107 and the lock pin 108 have to be accurately prepared with respect to each other. Moreover, there is a possibility that the lock pin 108 falls off because of excessive wear of the rubber member 104 after a long time of use.
Therefore, the applicant of the invention proposed a crawler shoe shown in FIG. 7 and disclosed in Japanese Kokai Publication Hei 9 (1997)-95267. The publication describes a band plate 29 having a hook fitting at one end and a nut 32 embedded near the other end. The hook fitting 31 provided at one end of the band plate 29 is engaged with one end of a shoe plate 22. The band plate 29 is overlaid with the shoe plate 22 by simply swinging the band plate 29 using the engaging point as a fulcrum. Finally, a bolt is inserted from the upper surface of the shoe plate 22 and screwed into the nut 32. In this way, the attachment of the band plate with the rubber pad has been further simplified, and the demounting or disassembling can be easily performed. Furthermore, this crawler shoe does not have to be particularly accurately manufactured since the band plate 29 is firmly fixed with the shoe plate 22 by screwing the bolt into the nut 32.
The attachment of the shoe member to the shoe plate was simplified in the above-mentioned crawler shoe proposed by the applicant of the present invention, which does not particularly need to be accurate. Therefore, the operational efficiency was improved. However, when the bolt is screwed against the nut 32 in the shoe plate 22 at the other end of the band plate 29, it is necessary to provide at least some alignment for the members attached to the shoe plate. Furthermore, the structure of the band plate 29 has to be changed for embedding the nut 32 therein. Moreover, a crawler made of iron should have two holes for screwing bolts therein. If there are no holes on the crawler, it is necessary to perform a perforation operation.
It is therefore an object of the present invention to provide a crawler prepared by solving the conventional problems, which improves the above-mentioned crawler shoe prepared by the applicant of the invention, and can be simply attached to a main body of the band plate 29, and which will not be easily loosened even when not being constructed very accurately.
To achieve the above-mentioned object, a crawler shoe according to the invention having shoe plates, to which shoe members having rubber pads are attached on ground contacting surfaces of the shoe plates, the shoe plates being connected with each other by connecting links each on the shoe plates with coupling pins in an endless form, comprises hook parts formed at first ends of the shoe members and configured to be engaged with first side parts of the shoe plates; side plates provided on the second ends of the shoe members for retaining the second side parts of the shoe plates; and retaining members provided on the side plates for holding and fixing the second side parts of the shoe plates, said retaining members being formed as spring pins, which can be made smaller and restored in a diameter direction, said spring pins being inserted into retaining holes formed in said side plates, and holding and fixing the second side parts of said shoe plates by pressing the upper surfaces of said shoe plates.
By having such structure, first, the hook parts provided at the first ends of the shoe members are engaged with the first ends of the shoe plates at engaging points; then, the shoe members are overlaid with the shoe plates by simply swinging the shoe members using the engaging points as fulcrums, and finally, retaining members are attached to the side plates. Only by such simple attachment, the second side parts of the shoe plates are securely damped and fixed, and will not be easily loosened. By the simple attachment performed by inserting and holding the spring pins into the side plates, the shoe members are attached to the shoe plates without loosening, and the demounting operation is also carried out extremely easily.
The crawler shoe is characterized in that the spring pins in the side plates are inserted and held in the side plate so as to downwardly slope from a retaining side portion to a non-retaining side portion, the non-retaining side portion being closer to the shoe plates to be held. Accordingly, the shoe plates can be more efficiently held by the elasticity of the spring pins.
The crawler shoe can be further characterized in that the hook members are covered with an elastic material. By having such structure, it is possible to more roughly prepare the hook parts because of the soft elastic material interposed between the hook members and the shoe plates.